Liquid heater



March 17, 1936. i H. TRElBER 2,034,123

' LIQUID HEATER Filed Oct. 17, 1935 BYQWM @ma Parental Mu. 17, 193ePATENT oFFlcE LIQUID HEATER Hans Treiber, Dessau. Germany, assigner toJunkers Co. G. m. b. H., Dessau, Germany l Application october V1'1,193s, sel-lai 10.45420 In January 14, 1932 4 calms. l(ci. zas-25) watersupply at a point in front ofthe controlvalve. This arrangement resultsin the disadvantage that even though the ilow of hot water to the mixingdevice is substantially constant the mixture supplied by the mixingdevice cannot be maintained at constant temperature because variationsof pressure in the supply line result in variations of the relativeproportion of hot and cold water to the mixing device.

It is the principal object of this invention to eliminate the abovementioned diculty. To this end the cold water supplied to the' mixingdevice is obtained from a point between the control valve and the heaterso that it is subject to regulation by the same member that controls theflow through the heater.

It is often desired to draw large quantities of 80 cold water alonethrough the outlet from the mixing device. It is a further object ofthis invention to provide a structure in which the flow of hot water tothemixing device may `be completely shut off without throttling the ilowof cold water, in spite of the fact that the ow of cold water isthrottled in proportion to the flow of hot water whenthe hot water valveis open. These and other objects and features of the invention will inpart be obvious to one skilled in the art and in part be set forth andmore-fully explained in the following detailed description taken inconjunction with the accompanying drawing which illustrates a preferredform of the invention with some parts in section and other parts in sideelevation.

Referring to the drawing, the coil or other heating element of theliquid heater is indicated as a iinned pipe I. The control system forthe heater includes a diaphragm housing having an upper part 2, a lowerpart 2 and a diaphragm 4 therebetween. As shown, the diaphragm 4 actingthrough stem 5 against spring 6 is adapted to actuate the gas valve 'Iwhich controls the dowof gas from a conduit 8 to a burner 9. A sleevevalve 25 is connected with the opposite side of diaphragm 4 and isadjustable to more or less restrictthe openings 26 in a stationary shell2'I.

A conduit I4 having a restricted entrance I 'I- connects the lowerdiaphragm chamber I5 to the heater I. A valve 20 in pipe 2l controls theilow of hot water from the heater I to the mixing device, the outletfrom which is indicated at 24. A cold water conduit 23 regulated'by cock22 is also connected to the diaphragm chamber I5. For convenience theconduits I4 and 23 may w branch oi from a single conduit opening intothe lower diaphragm chamber as shown. It will be understood that theconduits I4 and 23 may ,open into thelower diaphragm chamber throughseparate passages, it being important however 1;, that ilow of liquidfrom the diaphragm chamber I5 through conduit I4 be restricted as, at IIwhile vthe flow vfrom the diaphragm chamber through the conduit 23 berelatively unrestricted or only slightly restricted as at 30. Where theconduit 20 23 branches off from vrthe conduit I4 it is important thattheformer branch oli from a point in front of the restriction I1, ratherthan from a point behind the same. The upper 'diaphragm I8 is connectedby a passage to the conduit I4 25 in back of the restrictionV I1 asshown.

The system operates as follows:

Upon opening the hot water cock 20, cold water ows through pipe I3, theopenings 26. and thence through the hollow sleeve 25 into the lower 30diaphragm chamber I5.- From there the water ows through contraction I'land branch conduit I4 into the heater, and thence through conduit 2l tooutlet 24.- The difference in water pressure on the two sides ofcontraction I1 is transferred 35 to the diaphragm 4 in such manner thatits under side'is subjected to the greater pressure, which causes thediaphragm to ex upwardly. This iiexing of the diaphragm adjusts thesleeve valve 25 in such manner that, as soon as the pressure 40 ldierence effective on the diaphragm exceeds a predetermined amount thewater is throttled at f openings 26 .to such an extent that the pressurediierence eiective on the diaphragm is maintained constant at a valuedepending on the load 45 applied by spring 6 to the diaphragm. There-Qfore, a predetermined quantity of water I lows through branch I4 and isheated to the desired temperature in the heater I. If the cold watercock 22 is open also, then, so long as the hot 50 Water cock 20 is open,only a limited amount of b cold water can be obtained. This limitedquantity is suicient for heating purposes but cannot exceed the capacityof the heater to deliver water at a predetermined temperature. 55

nism. The burner 9 will of course be of such capacity as to supplysuiilcient heat to the water permitted to passv through conduit I4 toheat this water to the highest desired temperature.

Since the flow of water through the heater does not vary materially theheater I and the burner 9 may be correllated to function at a higheiiiciency and at temperatures which avoid condensation. The burner andheater therefore either operate under the most favorable conditions orare entirely out of operation.

In order to prevent, upon opening of the cock 22, water from flowingexclusively through branch 23, whereby no pressure diii'erence would beproduced at the diaphragm and the gas valve 1 would be closed, acontraction 30 is provided in branch 23, the cross section of which maybe considerably larger than that of the contraction I1. If the hot watercock 20 is closed, there is no more pressure diiierence at contractionl1, the diaphragm l moves downwardly under the influence ofspring 6, andthe'openings 2B of the guide shell 21 are entirely uncovered by means ofsleeve valve 25, so that then cold water may be obtained in largequantities over cock 22.

It will be seen .that the structure herein disclosed provides af systemwherein the proportion of hot and cold water supplied to a mixing devicemay be maintained constant for any given setting of the valves, therebymaintaining the water discharged from the, outlet of the deviceatconstant temperature. It will further be seen that the cold water maybe completely shut 01T without affecting the flow of hot water throughthe heater so that water at maximum temperature may be drawn from themixing device. Similarly cold water. alone may be drawn from the mixingdevice while the hot water is completely shut oi,

and furthermore the device may beset to supply waterat any desiredtemperature between these extremes and when so set the temperature llremain constant regardless of variations in l ressure of the supplysource.

' within the scope of the appended claims will be obvious to thoseskilled in the art.

Having thus described the invention what is claimed as new is:`

1. A system for regulating the ilow of hot and cold water to a hot andcold water mixing means, including a source of water supply, aregulating device for automatically controlling the flow from saidsource, a liquid heater, means for conducting water from said regulatingdevice through said heater and thence to said mixing means to supply hotwater thereto, and means to conduct water directly from said regulatingdevice to said mixing means to supply cold water thereto, whereby saidcontrol device regulates the' flow of both the hot water and the coldwater to said mixing means to maintain the relative proportions thereofconstant for any given setting thereof.

2. A system for regulating the ow of hot and cold water to a hot andcold water mixing means, including a source of supply, a regulatingdevice for automatically controlling the flow from said source, a liquidheater, means for conducting water from said regulating device to saidheater,l a connection between said heater and said mixing means, a hotwater cock controlling said connection, said regulating device operatingto maintain the ow of water through said heater constant when said cockis open, a connection between said regulating device and said mixingmeans for supplying cold water to the latter, a cold water cockcontrolling said connection and means whereby said regulating devicethrottles the flow of cold water to said mixing means when both saidcocks are open, while permitting unrestricted iiow of cold Water throughsaid cold water cock when said hot water cock is closed.

3. A system for regulating the flow of hot and cold water to a hot andcold water mixing means, including a hot water supply, a cold watersupply, separate cocks for controlling the flow of hot and cold waterfrom said supplies to said mixing device, and a common valve forcontrolling the iiow of both hot water and cold water to said mixingmeans, said common valve operating to maintain a constant flow of hotwater'to said mixing means when said-hot water cock is open, to restrictthe ow of cold water when bothY said cocks are open, and to permitunrestricted ow of cold water when said cold water cock alone is open.

4. A liquid heating and mixing system including a sourceof liquidsupply, a liquid heater, a connection between said heater and saidsource, a valve for maintaining the flow of liquid `through saidconnection constant regardless of variations in pressure at 'saidsource, a restriction in said connection between said heater and saidvalve, a mixing device, and connections for supplying hot water fromsaid heater to said device, and a cold water conduit connected to saidmixing device, said cold water conduit branchlng oi from said conduitleading to said heater at a point between said restriction and saidvalve..

HANS TREIBER.`

